Handling of data transfer in a LAN-free environment

ABSTRACT

There is disclosed a method, system and computer readable medium for transferring data in a LAN-free environment, in particular for a tape backup or restore operation. Data of a client partition of a first server is sent to a partition of a LAN-free server through the Local Area Network (LAN). The data sent is then converted from TCP/IP protocol to Fibre Channel protocol. The converted data is sent to a Storage Area Network (SAN) through a Fibre Channel card and finally to a tape library. An advantage is thus to mutualize and virtualize resources, in particular Fibre Channel cards. Storage Area Network tape drives are shared using such host bus adapter cards. Certain embodiments avoid the reconfiguration of Storage Area Network tape drives when the client partition moves to a new hardware.

CROSS-REFERENCE TO RELATED FOREIGN APPLICATION

This application is a non-provisional application that claims prioritybenefits under Title 35, United States Code, Section 119(a)-(d) fromEuropean (EP) Patent Application entitled “METHOD AND SYSTEM FORHANDLING DATA TRANSFER IN A LAN-FREE ENVIRONMENT” by Alain Lentini andJarl Theuwissen, having Patent Application No. EP09306262.8, filed onDec. 18, 2009, which EP Patent Application is incorporated herein byreference in its entirety.

BACKGROUND

1. Field

The disclosure relates to data processing, and more particularly to thehandling of data transfer in a LAN-free environment.

2. Background

Backup and restore operations pose various issues. In particular, backupon storage tape drives pose specific issues. For example, a same numberof backup cards and of partitions may be required. Some existingapproaches to solve these issues use particular communications systemsbetween servers of the architecture, other approaches mutualizeresources, and still other approaches leverage virtualizationmechanisms.

US Patent application 20080091896 entitled “Storage system and datamanagement method” for example discloses a storage system and a datamanagement method which can reduce the load on a virtualizationapparatus by executing backup processing or restoration processingwithin one apparatus in which an externally connected storage apparatusand a tape library apparatus are installed. The storage system includesa virtualization apparatus and an external storage apparatus, whereinthe virtualization apparatus comprises an actual volume for storing datasent from a host apparatus, formed in a storage area provided by aphysical disk. The virtualization apparatus further comprises a virtualvolume paired with the actual volume, for storing replicated data forthe data. The external storage apparatus comprises a logical volume thatfunctions as an actual storage area for the virtual volume and a tapeassociated with the logical volume, for storing the replicated data,wherein the external storage apparatus has a copy unit for copying thereplicated data stored in the logical volume to the tape. Whereas thisapproach leverages a virtualization mechanism, it still presentsdrawbacks.

During backup and restore operations, the use of the Local Area Network(LAN) may also be highly solicited, leading to a negative impact on thenetwork traffic for existing and active users. For this reason,“LAN-free” backups are increasingly operated. A LAN-free backup is abackup of the data of a server to a shared central storage devicewithout sending the data over the local area network (LAN).

There is a need for a system and method of efficiently managing backupor restore operations and in particular efficient handling of datatransfer in a LAN-free environment.

SUMMARY OF THE PREFERRED EMBODIMENTS

In order to address these and other problems, embodiments for handlingLAN-free data transfer are provided.

Certain embodiments relate to the usage of tape drives by virtualenvironments, and more particularly to the efficient connection of atape drive from a storage area network to a logical partition by using aVirtual LAN provided by a virtual environment.

Certain embodiments provide for the sharing Storage Area Network tapedrives using host bus adapter cards with several logical partitions.

Certain embodiments avoid the reconfiguration of Storage Area Networktape drives in the Operating System when the logical partition moves toa new hardware.

An advantage of certain embodiments relate to the sharing of FibreChannel (FC) technology in the context of LAN-free backup.

An additional advantage of certain embodiments is thus to shareresources between several servers.

Yet another advantage is to virtualize a Fibre Channel card betweenseveral servers.

Further advantages of certain embodiments will become clear to theskilled person upon examination of the drawings and detaileddescription. It is intended that any additional advantages beincorporated therein.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of certain aspects of the invention will now be describedwith reference to the following drawings, in which:

FIG. 1 shows a LAN-free server architecture design for an embodiment ofthe present invention;

FIG. 2 shows the live Partition Mobility design with LAN-free server;

FIG. 3 shows the workflow of the data transfer during a backup or arestore of the data;

FIG. 4 shows the workflow of the backup/restore protocol informationtransfer during a backup or a restore of the data;

FIG. 5 shows a workflow of a live Partition Mobility operation.

To facilitate description, any numeral identifying an element in onefigure will represent the same element in any other figure.

DETAILED DESCRIPTION

The following text presents embodiments in the context of LAN-freebackup or restore but it is to be understood that it is not limited tothis specific backup or restore context. In particular, the figures andthe description discuss a preferred embodiment with the use of IBMpSeries® servers. Further embodiments of the invention are notrestricted to these proprietary environments or products, which areprovided for exemplary purposes only.

A LAN-free backup is a backup of data from a server to a shared andcentral storage device. The goal of a LAN-free backup is to reduce theload on LAN and reduce the time required to complete the backup.

Therefore, such a LAN-free backup process often uses a Storage AreaNetwork (SAN). This type of backup offers an alternative way to backupdata: this is no more a simple data copy to network-attached storage(NAS) over LAN. There may exist a central backup server arbitratingaccess to devices (for all the other SAN servers), which does nothowever handle data stream itself. Without such a backup server, thestorage facility (usually a virtual tape library, or VTL) is adapted tohandle multiple data accesses without intermediate components.

Fibre Channel (FC), is a gigabit-speed network technology primarily usedfor storage networking FC ensures the connection between a computingdevice and the associated storage device. Fibre Channel is standardized:the ANSI working group X3T11 defines the Fibre Channel specifications.It has become the standard connection type for Storage Area Networks(SAN) in enterprise storage. Fibre Channel signaling can run on bothtwisted pair copper wire and fibre-optic cables. The Fibre ChannelProtocol (FCP) is a transport protocol which predominantly transportsSCSI commands over Fibre Channel networks.

FIG. 1 shows the LAN-free server architecture design. FIG. 1 comprises alogical partition which hosts a LAN-free backup client 100, a LAN-freeclient virtual Ethernet adapter dedicated to the data backup 101, avirtual Ethernet adapter LAN connectivity 102, a IBM pSeries® physicalserver 103, a Logical partition 120 that hosts a LAN-free server, aLAN-free server virtual Ethernet adapter 120 dedicated to data backup,LAN-SAN APIs 121 and 122 (the Storage Agent handles the communicationwith the backup server 140 over the LAN but sends the data directly toSAN attached tape library 160), a Virtual Input Output partition 130, aVirtual Ethernet server adapter 131 which is the interface betweenvirtual Ethernet clients and physical Ethernet LAN, a backup server 140,an Ethernet network adapter 141, a tape library 160, a Virtual LAN 180dedicated to the data backup, a Virtual LAN 181 dedicated for thenetwork communication, physical interfaces 184 connected to the storagearea network to send data to the library, the Local Area Network (LAN)187, a backup server connection 189 to the Local Area Network (LAN), atape library connection to the Storage Area Network (SAN) 190 and aStorage Area Network (SAN) 192.

In a typical design of a virtualized architecture, the physical server(IBM pSeries® for example) hosts several partitions 100 with operatingsystems used for production applications. These operating systems sharethe same physical resources owned by a specific partition. In FIG. 1this specific partition is named VIO server 130. In this architecture,the shared resources are used for LAN and SAN data communication.Virtualized structures to the interface between client partitions andthe physical interfaces hosted by the VIO partition 130 are required.

FIG. 1 shows the virtualized elements used for network LAN dataexchange: the Virtual Ethernet server adapter 131 is the interfacebetween virtual Ethernet clients and physical Ethernet LAN 187. For theproduction data access used by the client partitions 100, there may beused fibre channel cards owned by the VIO partition 130 and sharedbetween all the client partitions. These virtualizations provide ahardware sharing for LAN and SAN disks access to client partitions.

Certain embodiments of the invention provide a similar virtualization,but specifically for SAN tape sharing between client partitions 100. Thevirtualization consists in sharing fibre channel hardware cards 184connected to the SAN which is connected to the tape library. Theadvantage is thus to use few fibre channel hardware cards and share theminstead of installing one or more fibre channel hardware cards on eachclient partition.

In FIG. 1, the LAN-free server partition can be any of the clientpartition of the IBM pSeries® server.

In operation, in a first step data is transferred from the clientpartition 100 to the LAN-free server partition 120 that owns the fibrechannel cards and shares them with all client partitions. In certainembodiments, this step is operated using a virtual Ethernet LAN 180provided by the IBM pSeries® server 103 for example. A virtual LAN,commonly known as a vLAN, has the same attributes as a physical LAN, butdefines a logical grouping of networking devices. Networkreconfiguration can be operated through software (instead of physicallyrelocating devices). Alternatively to a vLAN, it may be a physical LANbut according to an embodiment, there is a sharing of hardware materialinstead of assignments of such material to particular tasks.

A second step is the conversion of data coming from virtual LAN 180 tosend it to the SAN fibre channel cards 184 to go then to the tapelibrary 160. This conversion is done by a tool currently named “APILAN-SAN” 122. In IBM environments, this API is named “LAN-free storageagent”. The API LAN-SAN enables the conversion from TCP (in the TCP/IPstack) into the FC protocol acting as a “gateway”. When data arereceived by the tape library 160, they are written on a set of tapesmanaged by the tape library. This mechanism can be initiated by a backupof the data owned by one of the client partitions 100 or by a restore ofthe data of one of client partitions 100. In case of a data backup,pieces of data come from the client partition 100 toward the tapelibrary 160, and in case of a data restore, pieces of data come from thetape library 160 toward one of the client partitions 100.

A backup or a restore of the client data is initiated and managed by oneof the backup server 140. To manage this backup or restore operation,the backup server communicates with the client partition. It usestherefore a physical LAN network 187. As the LAN hardware cards arevirtualized on the IBM pSeries® server models 103, they are hosted bythe VIO partition which shares them between available client partitions100 via a virtual LAN 181 provided by the IBM pSeries® server 103. Avirtual structure, the virtual Ethernet server adapter 131 is used togenerate the interface between physical and virtual LAN. During backupor restore operations, the backup server exchanges backup protocolinformation with the client partition.

FIG. 2 shows the Live Partition Mobility (LPM) design with LAN-freeserver. FIG. 2 comprises: a logical partition that hosts a LAN-freebackup client 200; a Logical partition that hosts a LAN-free server onthe server A 210; a Tape library 220; a Logical partition that hosts aLAN-free server on the server B 230; a Physical server A 240; a Physicalserver B 250; backup dedicated VLAN used for data transfer 261; aLAN-free client of IP address x.y.z.b, a virtual Ethernet adapter 262; aLAN-free server 263 of IP address x.y.z.3 (for example); a LAN-freeclient virtual Ethernet adapter 270 linked to the VIO; the Local AreaNetwork (LAN) 271 used for control and protocol streamed by the backupserver.

In case of live partition mobility (LPM), any client partition 100 canmove online from its IBM pSeries® 240 to the other IBM pSeries® 250dynamically. Certain embodiments include operations to perform thefollowing:

-   (i) SAN Tape Library Access After Live Partition Mobility    -   When the client partition 100 moves from the first IBM pSeries®        240 to the other IBM pSeries® 250, it can work with the LAN-free        server partition 230 owned by the other IBM pSeries®.    -   As the same IP address is defined on the LAN-free server        partition virtual Ethernet 263, the client partition IP address        262 can still communicate with the tape library via the new        LAN-free server partition 230.-   (ii) Data SAN Disks Client Partition Access After Live Partition    Mobility    -   The data SAN disks access is not interrupted during live        partition mobility. As each IBM pSeries® server is connected to        the same SAN, the Live Partition Mobility (LPM) copies the        virtual devices that manage the access to the SAN disks from the        source IBM pSeries® VIO partition 130 to the destination IBM        pSeries® VIO partition.-   (iii) Physical LAN Access From Client Partition After Live Partition    Mobility    -   The physical Local Area Network (LAN) 271 used for control and        protocol stream by the backup server 140 keeps connected during        the Live Partition Mobility (LPM). As the virtual structures        exist on the destination IBM pSeries® and are connected to the        same VLANs on the physical switches, the Live Partition Mobility        (LPM) connects the client partition 100 to the same VLANs after        the move. This means that the same backup server can continue to        control the backup or restore operations and the same tape        library can also be used after the move.-   (iv) LAN-Free Server Partition Access Via Virtual Ethernet LAN After    Live Partition Mobility    -   The dedicated VLAN 261 used for data transfer uses the same        subnet and the IP address is common for all LAN-free servers 263        hosted by the two physical servers (shown in the drawing as        physical server A 240 and as physical server B 250).    -   After the migration of the logical partition that hosts the        LAN-free client 200 from physical server IBM pSeries® A 240 to        the physical server IBM pSeries® B 250, the LAN-free client 200        is directly linked to the common IP address of the LAN-free        server 263. This configuration avoids any network or devices        reconfiguration.

FIG. 3 shows the workflow of the data transfer during a backup or arestore of the data. FIG. 3 describes the process of the data transferfrom the client partition 100 to the tape library 160 in case of abackup operation of the client data. In case of a restore operation, theprocess is similar but in the reverse direction.

At step 300, the data backup operation (or restore) is started on theLAN-free client 100.

At step 310, the client sends data to LAN-SAN API via virtual Ethernetclient adapter 101.

At step 320, the client Ethernet adapter transmits data through virtualLAN 180.

At step 330, the Virtual LAN transmits data to virtual Ethernet clientadapter 121.

At step 340, the virtual Ethernet client adapter transmits data toLAN-free storage agent 122.

At step 350, the LAN-SAN API sends data to tape library via SAN physicalinterfaces 184.

At step 360, the SAN connection transmits data to tape library (SANconnection of Tape library 190).

At step 370, the data is written on tape library 160 until the end ofthe backup.

At step 380, if the data backup is not finished, the process returns tostep 310.

FIG. 4 shows the workflow of the backup/restore protocol informationtransfer during a backup or a restore of the data. The workflow shown onFIG. 4 describes the process of backup protocol information exchangebetween the client partition 100 and the backup server 140 to manage thebackup or restore of the data of the client partition 100.

At step 400, the data backup (or restore) is started on the LAN-freeclient 100.

At step 410, the client exchanges Protocol Information with backupserver via virtual Ethernet client adapter 102.

At step 420, the virtual Ethernet client adapter transmits or receivesProtocol Information through the virtual LAN 181.

At step 430, the virtual LAN transmits/receives Protocol Informationto/from VIO server 130.

At step 440, the VIO server transmits/receives Protocol Informationto/from virtual Ethernet server adapter 131.

At step 450, the virtual Ethernet server adapter transmits/receivesProtocol Information to/from Ethernet adapter 141 of the backup server140.

At step 460, the Physical Ethernet adapter of the backup servertransmits/receives Protocol Information to backup server 140.

FIG. 5 shows a workflow of a live Partition Mobility operation.

The LAN-free client 200 sends the data of the backup through thededicated VLAN 261 to the IP address dedicated to the LAN-free servers263. The LAN-free servers are hosted on different physical servers (inthe figure, as physical server A 240 and physical server B 250).

LAN-free servers are attached by Storage Area Network SAN 271 to theTape library. The LAN-free clients, LAN-free servers and backup server221 are connected to a Local Area Network LAN 271 providing the controland protocol information.

Alterations and modifications may be made to the above without departingfrom the scope of the invention. Naturally, in order to satisfy localand specific requirements, a person skilled in the art may apply to thesolution described above many modifications and alterations.Particularly, although the present invention has been described with acertain degree of particularity with reference to preferredembodiment(s) thereof, it should be understood that various omissions,substitutions and changes in the form and details as well as otherembodiments are possible; moreover, it is expressly intended thatspecific elements and/or method steps described in connection with anydisclosed embodiment of the invention may be incorporated in any otherembodiment as a general matter of design choice.

For example, similar considerations apply if the computers havedifferent structure or include equivalent units; in any case, it ispossible to replace the computers with any code execution entity (suchas a PDA, a mobile phone, and the like).

Similar considerations apply if the program (which may be used toimplement each embodiment of the invention) is structured in a differentway, or if additional modules or functions are provided; likewise, thememory structures may be of other types, or may be replaced withequivalent entities (not necessarily consisting of physical storagemedia). Moreover, the proposed solution lends itself to be implementedwith an equivalent method (having similar or additional steps, even in adifferent order). In any case, the program may take any form suitable tobe used by or in connection with any data processing system, such asexternal or resident software, firmware, or microcode (either in objectcode or in source code). Moreover, the program may be provided on anycomputer-usable medium; the medium can be any element suitable tocontain, store, communicate, propagate, or transfer the program.Examples of such medium are fixed disks (where the program can bepre-loaded), removable disks, tapes, cards, wires, fibres, wirelessconnections, networks, broadcast waves, and the like; for example, themedium may be of the electronic, magnetic, optical, electromagnetic,infrared, or semiconductor type.

In any case, the solution according to the present invention lendsitself to be carried out with a hardware structure (for example,integrated in a chip of semiconductor material), or with a combinationof software and hardware.

Embodiments can thus take form of an entirely hardware embodiment, anentirely software embodiment or an embodiment containing both hardwareand software elements. Certain embodiments are implemented in software,which includes but is not limited to firmware, resident software,microcode, etc. In a high performance system, a hardware implementationof the virtualization mechanism bundled with image generation processingmay prove advantageous for example.

Furthermore, certain embodiments can take the form of a computer programproduct accessible from a computer-usable or computer-readable mediumproviding program code for use by or in connection with a computer orany instruction execution system. For the purposes of this description,a computer-usable or computer-readable medium can be any apparatus thatcan contain, store, communicate, propagate, or transport the program foruse by or in connection with the instruction execution system,apparatus, or device.

IBM pSeries® is a registered trademark of IBM Corporation

What is claimed is:
 1. A system for handling data transfer, the systemcomprising: a first server; and a LAN-free server coupled to the firstserver, wherein the system performs operations, the operationscomprising: sending data from the at least one client partition of thefirst server to at least one partition of the LAN-free server through aLocal Area Network (LAN) on TCP/IP protocol, wherein the sendingcomprises: transmitting the data from a first virtual adapter through avirtual LAN to a second virtual adapter; and transmitting, by the secondvirtual adapter, the data to a LAN-free storage agent comprising aLAN-SAN Application Programming Interface (API); converting the sentdata from the TCP/IP protocol into Fibre Channel protocol; and sendingthe converted data to a tape library of a Storage Area Network (SAN)through at least one Fibre Channel card, wherein SAN tape sharing isperformed between client partitions via virtualization by sharing FibreChannel cards coupled to the SAN which is coupled to the tape library,wherein no Fibre Channel cards are installed on each of the clientpartitions, wherein the virtual LAN has same attributes as a physicalLAN but defines a logical grouping of networking devices, and whereinthe at least one client partition is configured to move dynamicallybetween servers via live partition mobility (LPM).
 2. The system ofclaim 1, wherein the data transfer is performed in a LAN-freeenvironment, and wherein the LAN-free environment comprises: the SANhaving at least one tape library; the LAN-free server having the atleast one partition; and the first server having the at least one clientpartition, wherein the LAN-free server further has the at least oneFibre Channel card shared with the at least one client partition.
 3. Thesystem of claim 2, wherein the converting is performed by the LAN-SANApplication Programming Interface (API), the API acting as a gateway. 4.The system of claim 2, wherein the LAN-free environment furthercomprises a backup server coupled to the client partition, and whereinthe backup server initiates the data transfer.
 5. The system of claim 2,the operations further comprising: moving the at least one clientpartition from the first server to a second server.
 6. The system ofclaim 1, wherein in LPM, network or devices reconfiguration is avoidedvia direct linkage of the at least one client partition to a commoninternet protocol (IP) address of the LAN-free server.
 7. The system ofclaim 6, wherein in LPM, virtual devices that manage access to SAN disksare copied from a source partition to a destination partition.
 8. Anon-transitory computer readable medium for handling data transferhaving encoded thereon a computer program, when said computer program isexecuted on a suitable computer to perform operations, the operationscomprising: sending data from at least one client partition of a firstserver to at least one partition of a LAN-free server through a LocalArea Network (LAN) on TCP/IP protocol, wherein the sending comprises:transmitting the data from a first virtual adapter through a virtual LANto a second virtual adapter; and transmitting, by the second virtualadapter, the data to a LAN-free storage agent comprising a LAN-SANApplication Programming Interface (API); converting the sent data fromthe TCP/IP protocol into Fibre Channel protocol; and sending theconverted data to a tape library of a Storage Area Network (SAN) throughat least one Fibre Channel card, wherein SAN tape sharing is performedbetween client partitions via virtualization by sharing Fibre Channelcards coupled to the SAN which is coupled to the tape library, whereinno Fibre Channel cards are installed on each of the client partitions,wherein the virtual LAN has same attributes as a physical LAN butdefines a logical grouping of networking devices, and wherein the atleast one client partition is configured to move dynamically betweenservers via live partition mobility (LPM).
 9. The non-transitorycomputer readable medium of claim 8, wherein the data transfer isperformed in a LAN-free environment, and wherein the LAN-freeenvironment comprises: the SAN having at least one tape library; theLAN-free server having the at least one partition; and the first serverhaving the at least one client partition, wherein the LAN-free serverfurther has the at least one Fibre Channel card shared with the at leastone client partition.
 10. The non-transitory computer readable medium ofclaim 9, wherein the converting is performed by the LAN-SAN ApplicationProgramming Interface (API), the API acting as a gateway.
 11. Thenon-transitory computer readable medium of claim 9, wherein the LAN-freeenvironment further comprises a backup server coupled to the clientpartition, and wherein the backup server initiates the data transfer.12. The non-transitory computer readable medium of claim 9, theoperations further comprising: moving the at least one client partitionfrom the first server to a second server.
 13. The non-transitorycomputer readable medium of claim 8, wherein in LPM, network or devicesreconfiguration is avoided via direct linkage of the at least one clientpartition to a common Internet Protocol (IP) address of the LAN-freeserver.
 14. The non-transitory computer readable medium of claim 13,wherein in LPM, virtual devices that manage access to SAN disks arecopied from a source partition to a destination partition.